The question was not about traffic. It was about how the different platforms compare from a technical point of view. One point could be how they can handle traffic, i.e. will one become slower and break down, while the other can handle the load better?

Hi sanit. Obviously you'll have to fully compare the platforms for yourself, but I can tell you that Q2A is very scalable, in that it is designed to handle millions of users and/or posts, by using appropriate database indexes and the like.

Shapado is an open source question-answer system written in Ruby, Mongomapper and MongoDB.

Question2Answer is a free, Open Source php Q&A system.

OSQA (Open Source Question and Answer) is an open source question-answer system written in Python with Django. The data layer relies on Mysql or Microsoft Sql Server. OSQA is licensed under GPL version 3 or later.

While OSQA is also good, uses Django/Python as platform. (which is not as widespread, Althoug the Bitnami distribution seems to work fine. One thing I did not like about Django is that the Django_session table grows very large (which made impractical for me to host it on the free tier of heroku). Also there is no much development these days). I like the OpenId loginm which look more polished than the one here in Q2A, also python looks like an easier language to start (if you have no php knowledge)